Reciprocating fluid pumps are used in many industries. Reciprocating fluid pumps generally include two fluid chambers in a pump body. A reciprocating piston or shaft is driven back and forth within the pump body. One or more diaphragms or bellows plungers may be connected to the reciprocating piston or shaft. As the reciprocating piston moves in one direction, the movement of the diaphragms or bellows plungers results in fluid being drawn into a first fluid chamber of the two fluid chambers and expelled from the second chamber. As the reciprocating piston moves in the opposite direction, the movement of the diaphragms or bellows plungers results in fluid being expelled from the first chamber and drawn into the second chamber. A chamber inlet and a chamber outlet may be provided in fluid communication with the first fluid chamber, and another chamber inlet and another chamber outlet may be provided in fluid communication with the second fluid chamber. The chamber inlets to the first and second fluid chambers may be in fluid communication with a common single pump inlet, and the chamber outlets from the first and second fluid chambers may be in fluid communication with a common single pump outlet, such that fluid may be drawn into the pump through the pump inlet from a single fluid source, and fluid may be expelled from the pump through a single pump outlet. Check valves may be provided at the chamber inlet and outlet of each of the fluid chambers to ensure that fluid can only flow into the fluid chambers through the chamber inlets, and fluid can only flow out of the of the fluid chambers through the chamber outlets.
Examples of such reciprocating fluid pumps are disclosed in, for example, U.S. Pat. No. 5,370,507, which issued Dec. 6, 1994 to Dunn et al., U.S. Pat. No. 5,558,506, which issued Sep. 24, 1996 to Simmons et al., U.S. Pat. No. 5,893,707, which issued Apr. 13, 1999 to Simmons et al., U.S. Pat. No. 6,106,246, which issued Aug. 22, 2000 to Steck et al., U.S. Pat. No. 6,295,918, which issued Oct. 2, 2001 to Simmons et al., U.S. Pat. No. 6,685,443, which issued Feb. 3, 2004 to Simmons et al., and U.S. Pat. No. 7,458,309, which issued Dec. 2, 2008 to Simmons et al., the disclosure of each of which is incorporated herein in its entirety by this reference.